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Enhanced Model Stormwater Ordinance for Municipalities

Municipalities in New Jersey are required to adopt a Municipal Stormwater Control ordinance reflecting various amendments made to the Stormwater Management Rule (N.J.A.C. 7:8) by the New Jersey Department of Environmental Protection (NJDEP). To assist municipalities in adopting stormwater ordinances, New Jersey Future developed this Enhanced Model Ordinance. It is based on Appendix D: Model Stormwater Control Ordinance for Municipalities of the NJ Stormwater Best Management Practices Manual provided by NJDEP, and includes modifications beyond the minimum to provide for improved water quality, more widespread implementation of green infrastructure, and greater protection of water resources. This sample ordinance is provided for information purposes only. It is important that amended rules are carefully reviewed before any portion of this draft ordinance is adopted. This ordinance is intended to apply to major and minor developments not pre-empted by the Residential Site Improvement Standards at N.J.A.C. 5:12.

Stormwater management aims to minimize pollution caused by stormwater in order to restore, enhance, and maintain the integrity of waters of the state. Federal, as well as state, water pollution laws permit municipalities to undertake additional actions including ordinances with standards stronger than the statewide minimum requirements N.J.A.C. 7:8-1.5(a). A municipality may choose stronger or additional measures, beyond the minimum standards and expectations set forth in N.J.A.C. 7:8, to improve local water quality, mitigate flood risk, and/or address other environmental or community needs.

New Jersey Future (NJF) recognizes the stormwater challenges faced by municipalities within the state, including water pollution and flooding. The 2016 New Jersey Integrated Water Quality Assessment Report acknowledges a majority of waterways are impaired for at least one designated use. In the 2020 New Jersey Scientific Report on Climate Change, NJDEP projections include increased annual precipitation, increased intensity and frequency of precipitation events, increased size and frequency of flooding, and decreased surface and groundwater quality due to increased runoff.

Municipalities may have various reasons for enacting more stringent stormwater requirements. This Enhanced Model Stormwater Ordinance offers guidance on the following enhancements to achieve effective stormwater management:

· Reducing the threshold for “Major Development”. This may allow a municipality with dense and smaller developments implement effective stormwater management and its associated benefits of flood reduction and improved water quality.

· Providing a definition, stormwater management requirements, and maintenance for “Minor Development”. This may capture very small projects that collectively contribute an increase of stormwater runoff to a vulnerable area.

· Modifying the definition of “Regulated impervious surface” to include all impervious surface within the project area, instead of net increase of impervious surface, thereby capturing redevelopment projects. A more holistic enhancement that addresses all impervious, not just the net increase of impervious, may allow impaired waterways to benefits from stormwater management of not only new impervious, but those existing impervious surfaces that have been a contribution to the poor integrity of stream channels including biological, ecological, and recreational functions.

· Reducing the contributory drainage areas for green infrastructure best management practices (BMPs). Addressing contributory drainage areas leads to a distributed approach that enhances the reliability and effectiveness of a stormwater management design to function as intended and address all the goals of stormwater management planning.

· Modifying the Groundwater Recharge Standard to include an “onsite retention” requirement. Promoting volume management through infiltration aims to directly address flooding, stormwater runoff, and groundwater recharge.

· Modifying the Stormwater Runoff Quality Standard to include regulated impervious areas. Providing water quality treatment for all impervious areas, not just motor vehicular surfaces, will minimize non-point source pollution and those pollutants in stormwater runoff leading to waters of the State.

All of the aforementioned options provide varying benefits. A municipality may elect to incorporate one or more of these options depending on the specific needs and desires of the municipality

How to read and use this enhanced model ordinance:

This Enhanced Model Stormwater Ordinance for Municipalities provided by New Jersey Future is based on Appendix D: Model Stormwater Control Ordinance for Municipalities of the NJ Stormwater Best Management Practices Manual provided by NJDEP. Please note that these ordinance enhancements are NOT an official requirement of NJDEP. The intent of this Enhanced Model Stormwater Ordinance is to provide New Jersey municipalities with information for review, reference, and consideration. This model ordinance is not intended as a substitute for legal advice. Municipalities should consult with their attorney(s) before adopting a stormwater ordinance to ensure that the submitted ordinance submitted complies with all aspects of federal, state, and local law.

· Original text by NJDEP is in black standard text.

· Original notes by NJDEP are in black italicized text and are not intended to be adopted as part of the ordinance.

· Modified or added text by NJF is in blue standard text.

· Modified or added notes by NJF are in blue italicized text and are not intended to be adopted as part of the ordinance.

· In some instances, NJF provides a menu of options in red italicized text, where only one option from the menu of options is intended to be selected and the remainder of the text is not intended to be adopted as part of the ordinance.

About New Jersey Future

Founded in 1987, New Jersey Future is a nonprofit, nonpartisan organization that promotes sensible growth, redevelopment, and infrastructure investments to foster vibrant cities and towns, protect natural lands and waterways, enhance transportation choices, provide access to safe, affordable, and aging-friendly neighborhoods, and fuel a strong economy. This Enhanced Model Stormwater Ordinance for Municipalities is a product of New Jersey Future’s Mainstreaming Green Infrastructure program.

For more information, please visit New Jersey Future’s stormwater resources:

· New Jersey Green Infrastructure Municipal Toolkit

· New Jersey Developers Green Infrastructure Guide

· New Jersey Stormwater Utilities Resource Center

Introduction 2

New Jersey Future Enhanced Model Stormwater Ordinance for Municipalities

Guidance Table to the Enhanced Model Stormwater Ordinance for Municipalities

How to read and use this guidance table:

This table is to be used as a comparative reference guide for identifying enhancements that appear in the New Jersey Future Enhanced Model Stormwater Ordinance for Municipalities. These enhancements are suggested modifications and additions to the New Jersey Department of Environmental Protection (NJDEP) Model Stormwater Control Ordinance for Municipalities appearing in Appendix D of the New Jersey Stormwater Best Management Practices Manual.

Rows contain substantive changes. Column 1 identifies the Section Title in which the suggested modification or addition appears. Column 2 describes information as it appears in the NJDEP version. Column 3 describes how this information appears in the New Jersey Future Enhanced Model Stormwater Ordinance for Municipalities. Column 4 contains supporting options or notes for the enhancement, including suggested options for some criteria. Note that while the Section Title in Column 1 does not vary between the two versions, the section numbering may have changed and has been identified in Columns 2-4.

· In this table, black standard text is both original ordinance text by NJDEP or descriptive language (for example: “Modification…” or “Revised…” or “Includes…)

· Modified or added ordinance text by New Jersey Future is noted blue standard text.

· Modified or added notes by New Jersey Future are in blue italicized text and are not intended to be adopted as part of the ordinance.

· In some instances, New Jersey Future provides a menu of options in red italicized text, where only one option from the menu of options is intended to be selected.

This table is not intended to be adopted as part of the ordinance.

This page is intentionally left blank.

Guidance Table 3


Section Title

New Jersey Department of Environmental ProtectionModel Stormwater Control Ordinance for Municipalities(Minimum requirements)


(Suggested modifications and additions)


(Options and notes)

Scope and Purpose

Section I

Section I

Section I

Policy Statement

Policy Statement revised.

Jump to location below.

Does not include references to “minor development.”

Revised language to include “minor development” to Section I.B. and Section I.C.


Notes:

- Minor development does not appear in the NJDEP Model Stormwater Control Ordinance for Municipalities. Municipalities may choose to implement more stringent measures, such as defining and regulating minor developments. Inclusion of minor developments, as separate from major developments, allows a municipality to set a threshold and management rules appropriate for minor developments. Including Minor development can assist municipalities in regulating stormwater management of smaller projects, which can have a significant stormwater contribution.

- Each municipality should include objectives as appropriate. For example, this ordinance includes a “stormwater retention requirement” that, in some cases, will require greater onsite capture of runoff than is required under the minimum state standards; this ordinance also applies to many developments under one acre in size, which are not covered by the minimum state standards.

- N.J.A.C. 7:8-4.2(c)(8) requires municipalities to modify land use plans and zoning ordinances as necessary to facilitate implementation of the non-structural strategies of this model ordinance. Additionally, N.J.S.A. 40:44D-93 requires municipalities to review their stormwater master plans each time they reexamine or review their land use master plans. In connection with adoption of a model ordinance, municipalities are strongly encouraged to review and update their existing land use plans and zoning ordinances to promote compliance not only with non-structural strategies, but with all provisions of this ordinance.

Applicability:

1. This ordinance shall be applicable to the following major developments:

a. Non-residential major developments; and

b. Aspects of residential major developments that are not pre-empted by the Residential Site Improvement Standards at N.J.A.C. 5:21.

2. This ordinance shall also be applicable to all major developments undertaken by [insert name of municipality].

Modified Applicability:

1. This ordinance shall be applicable to the following major and minor developments:

a. Non-residential major and minor developments; and

b. Aspects of residential major and minor developments that are not pre-empted by the Residential Site Improvement Standards at N.J.A.C. 5:21.

2. This ordinance shall also be applicable to all major and minor developments undertaken by [insert name of municipality].

3. This ordinance shall also be applicable to all major and minor developments as applicable under I.C.1. and I.C.2., whether public or private.


Table continues next page

Section Title





(Options and notes)

Definitions

Section II

Section II

Section II

Does not include a definition for “Low Impact Development”

Includes definition for “Low Impact Development”:

“Low impact development” means a development approach that uses practices to manage stormwater close to its source that results in or mimics that of natural hydrologic processes in order to preserve hydrologic and ecologic functions of receiving waters, such as preservation of natural landscape features, minimizing impervious surfaces, infiltration, evapotranspiration, or other use of stormwater.


Notes:

- This definition was adapted from an EPA description of low impact development.

“Major development” definition:

1. The disturbance of one or more acres

2. The creation of one-quarter acre or more of “regulated impervious surface”

3. The creation of one-quarter acre or more of “regulated motor vehicle surface”

4. A combination of 2 and 3 above that totals an area of one-quarter acre or more.

Modification of “Major development” definition:

1. The disturbance of ½ acre (21,780 square feet) or more

2. The creation of 5,000 square feet or more of “regulated impervious surface”

3. The creation of 5,000 square feet or more of “regulated motor vehicle surface”

4. A combination of 2 and 3 above that totals an area of 5,000 square feet or more.


Modification of “Major development” definition:

1. The disturbance of [15,000 square feet / ½ acre (21,780 square) feet / ¾ acre (32,670 square feet)] or more

2. The creation of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more of “regulated impervious surface”

3. The creation of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more of “regulated motor vehicle surface”

4. A combination of 2 and 3 above that totals an area of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more.

Notes:

- The threshold options provided above are suggestions only. Municipalities should evaluate the appropriate threshold level based on their knowledge and goals for the municipality.

- Municipalities should evaluate municipal resources available that may be affected by this change (for example: review, permit, and enforcement).

- New Jersey Future suggests ½ acre (21,780 square feet) for item 1 of the definition and 5,000 square feet for items 2-4 of the definition. These suggestions offer enhanced stormwater management, without impacting very small projects. By selecting a disturbance threshold below the minimum 1 acre of disturbance required by NJDEP, stormwater management will become a requirement for a larger number of projects, advancing the pace of stormwater improvements. The selection of 5,000 square feet for “regulated impervious surfaces” and “regulated motor vehicle surfaces” was selected as a threshold to align with the 5,000 square feet of disturbance project limit appearing in the Soil Erosion and Sediment Control Act.

Table continues next page.

Section Title





(Options and notes)

Definitions

Section II

Section II

Section II

Does not include a definition for “Minor Development”

Includes definition for “Minor Development”:

“Minor Development” means an individual “development,” as well as multiple developments that individually or collectively result in 2,500 square feet of disturbance, but do not meet the definition for “Major Development.”


Includes definition for “Minor Development”:

“Minor Development” means an individual “development,” as well as multiple developments that individually or collectively result in [500 square feet / 1,000 square feet / 2,500 square feet] of disturbance but do not meet the definition for “Major Development.”

Notes:

- Including a definition and threshold of “Minor development” can assist municipalities in regulating stormwater management of smaller projects, which can have a significant stormwater contribution, particularly in dense areas.

- The inclusion of “Minor Development” the threshold options above are suggestions only. Municipalities should evaluate inclusion of the definition and an appropriate threshold level based on their knowledge and goals for the municipality.


- The threshold for “Minor Development” should not conflict with the definition of “Major Development.”

- New Jersey Future suggests a threshold for “Minor Development” of 2,500 square feet, which will provide a reduced level of stormwater management for some smaller projects without impacting very small improvements. Small, incremental increases in impervious can have a cumulative impact on flooding and water quality. Including “Minor Development” may also serve to bring awareness to communities regarding the impact of small project on community stormwater impacts.

“Regulated impervious surface” definition:

1. A net increase of impervious surface

2. The total area of impervious surface collected by a new stormwater conveyance system

3. The total area of impervious surface proposed to be newly collected by an existing stormwater conveyance system

4. The total area of impervious surface collected by an existing stormwater conveyance system where the capacity of that conveyance system is increased

Modifies “Regulated impervious surface” definition:

1. All impervious surface within the project area limit of disturbance

2. The total area of impervious surface collected by a new stormwater conveyance system

3. The total area of impervious surface proposed to be newly collected by an existing stormwater conveyance system

4. The total area of impervious surface collected by an existing stormwater conveyance system where the capacity of that conveyance system is increased


Notes:

- By modifying the definition from “net increase of impervious surface” to “all impervious surface within the project area,” criteria for item (2.) under the definition for “Major Development” is modified to indicate a threshold on all post-development impervious surfaces, regardless of existing condition.

- Many areas are experiencing adverse impact (flooding, poor water quality) under existing conditions. Requiring stormwater management for post-development impervious surfaces offers an opportunity for municipalities to address stormwater management impacts from a built condition.

“Site” definition:

“Site” means the lot or lots upon which a major development is to occur or has occurred.

“Site” definition revised to include “minor development”:

“Site” means the lot or lots upon which a major or minor development is to occur or has occurred.



Section Title





(Options and notes)

Design and Performance Standards for Stormwater Management Measures

Section III

Section III

Section III

Does not include references to “minor development.”

Revised language to include “minor development” to Section III.B.


Stormwater Management Requirements for Major Developments

Section IV

Section IV

Section IV

Table in Section IV.O.2.:

Best Management Practice

Maximum Contributory Drainage Area

Dry Well

1.0 acre

Manufactured Treatment Device

2.5 acres

Pervious Pavement Systems

Area of additional inflow cannot

exceed three times the area

occupied by the BMP

Small-scale Bioretention Systems

2.5 acres

Small-scale infiltration basin

2.5 acres

Small-scale sand filter

2.5 acres

Modified Table in Section IV.O.2.:



Dry Well

0.5 acre


1.0 acre



exceed two times the area

occupied by the BMP


1.0 acre


1.0 acre


1.0 acre


Modified Table in Section IV.O.2.:



Dry Well

[0.25 / 0.5 / 0.75] acre


[0.5 / 1.0 / 1.5] acre



exceed [one / two] times the area

occupied by the BMP


[0.5 / 1.0 / 1.5] acre


[0.5 / 1.0 / 1.5] acre


[0.5 / 1.0 / 1.5] acre

Notes:

- The various options provided above are suggestions only. Municipalities should evaluate the appropriate level on their knowledge and goals for the municipality.

- Reducing maximum contributory drainage areas will lead to more stormwater best management practices that are distributed on the site, a key component of low impact development. This reduces the risk of damage if any one system is overloaded or experiences failure.- Reduced loading rates onto pervious pacing systems maintain the intended benefits of the system. Additional areas loaded onto the porous pavement systems increases the potential for sediment and pollutant loading, which overtime can lead to failure of systems.


Section Title





(Options and notes)


Section IV

Section IV

Section IV

Criteria for Groundwater Recharge Standard, Section IV.P.2.:

2. The design engineer shall, using the assumptions and factors for stormwater runoff and groundwater recharge calculations in Section V, either:

i. Demonstrate through hydrologic and hydraulic analysis that the site and its stormwater management measures maintain 100 percent of the average annual pre-construction groundwater recharge volume for the site; or

ii. Demonstrate through hydrologic and hydraulic analysis that the increase of stormwater runoff volume from pre-construction to post-construction for the 2-year storm is infiltrated.

Modified criteria for Groundwater Recharge Standard, Section IV.P.2.:

2. The design engineer shall, using the assumptions and factors for stormwater runoff and groundwater recharge calculations in Section VI, the following criteria that results in the greatest infiltration volume:


ii. Demonstrate through hydrologic and hydraulic analysis that the increase of stormwater runoff volume from pre-construction to post-construction for the 2-year storm is infiltrated; or

iii. Demonstrate through hydrologic and hydraulic analysis that 1.5 inches over all impervious surfaces is infiltrated or retained on site.


Modified criteria for Groundwater Recharge Standard, Section IV.P.2.:

IV.P.2.iii: Demonstrate through hydrologic and hydraulic analysis that [1.0 / 1.25 / 1.5] inches over all impervious surfaces is infiltrated.

Notes:

- This modification requires a volume equal to or greater than the precipitation depth over impervious surfaces to be infiltrated or retained on site.

- Infiltration of stormwater from onsite impervious will achieve several stormwater management goals, including reduced flooding, improved water quality, and increased groundwater recharge.

Does not include onsite retention volume.

Include information where onsite retention volume cannot be infiltrated, reused, or evapotranspired.



Section Title





(Options and notes)


Section IV

Section IV

Section IV

Stormwater Runoff Quality Standards IV.Q.:

1. This subsection contains the minimum design and performance standards to control stormwater runoff quality impacts of major development. Stormwater runoff quality standards are applicable when the major development results in an increase of one-quarter acre or more of regulated motor vehicle surface.

2. Stormwater management measures shall be designed to reduce the post-construction load of total suspended solids (TSS) in stormwater runoff generated from the water quality design storm as follows:

i. Eighty percent TSS removal of the anticipated load, expressed as an annual average shall be achieved for the stormwater runoff from the net increase of motor vehicle surface.

ii. If the surface is considered regulated motor vehicle surface because the water quality treatment for an area of motor vehicle surface that is currently receiving water quality treatment either by vegetation or soil, by an existing stormwater management measure, or by treatment at a wastewater treatment plant is to be modified or removed, the project shall maintain or increase the existing TSS removal of the anticipated load expressed as an annual average.

Modifies Stormwater Runoff Quality Standards IV.Q.:

1. This subsection contains the minimum design and performance standards to control stormwater runoff quality impacts of major development. Stormwater runoff quality standards are applicable when the major development results in:

i. Creation of 5,000 square feet or more of regulated motor vehicle surface, and/or

ii. Creation of 5,000 square feet or more of regulated impervious surface.


i. Eighty percent TSS removal of the anticipated load, expressed as an annual average shall be achieved for the stormwater runoff from regulated motor vehicle surfaces and regulated impervious surfaces.

ii. If the surface is considered regulated motor vehicle surface because the water quality treatment for an area of motor vehicle surface that is currently receiving water quality treatment either by vegetation or soil, by an existing stormwater management measure, or by treatment at a wastewater treatment plant is to be modified or removed, the project shall maintain or increase the existing TSS removal of the anticipated load expressed as an annual average.


Notes:

- The selection here should be consistent with the threshold defined in the definition of “Major Development.”

- The current rule applies the runoff quality standard to the increase of regulated motor vehicle surfaces only, which does little to protect water quality from existing motor vehicle surfaces, as well as sidewalks, plazas, rooftops, etc. which do contribute to pollution of water quality through sediments, spills, animal waste, seasonal salting, etc. By modifying criteria to include regulated motor vehicle surfaces and regulated impervious surfaces, water quality treatment can be addressed across an entire development site.

- These changes would treat water quality of impervious surfaces based on water quality conditions noted in the 2016 Integrated Report and anticipated adverse water quality affects associated with increased frequency and intensity of precipitation noted in the 2020 New Jersey Scientific Report on Climate Change.


Section Title





(Options and notes)

Stormwater Management Requirements for Minor Developments

Does Not Contain Section

Section V

Section V

Does not contain stormwater management requirements for “Minor Development”

Includes section on stormwater management of projects meeting the definition of “Minor Development” including:

3. The design engineer shall, using the assumptions and factors for stormwater runoff and groundwater recharge calculations at Section VI, the following criteria:

i. Demonstrate through hydrologic and hydraulic analysis that the first 1.0 inches from all impervious surfaces within the project limit of disturbance is retained onsite through infiltration, reuse, evapotranspiration or other acceptable engineering methods.


Notes:

- Maintenance is an important aspect to prolong the lifetime of stormwater management systems. Requiring a maintenance plan for “Minor Development” should be evaluated by the municipality.

- Requiring stormwater management for “Minor Developments” can be an important tool for municipalities that see adverse stormwater impacts that result from the cumulative impact of small projects.

- By reducing the requirements to a single standard for Minor Development, the process should be simplified for both the applicant and the reviewing entity.


- Infiltration of small storms will achieve several stormwater management goals, including reduced flooding, improved water quality, and increased groundwater recharge.

- The volume management requirement for “Minor Developments” is a reduced volume as compared to “Major Developments,” which may incentive projects to reduce project disturbance and creation of impervious surfaces.

Calculation of Stormwater Runoff and Groundwater Recharge

Section V

Section VI

Section VI

Section Title: Calculation of Stormwater Runoff and Groundwater Recharge

Section Title: Calculation of Stormwater Runoff, Onsite Retention, and Groundwater Recharge

Calculation of onsite retention not addressed.

Added guidance on calculation of onsite retention volume.


Sources for Technical Guidance

Section VI

Section VII

Section VII

No modification to section.

No modification to section. Section number updated based on insertion of section.

Solids and Floatable Materials Control Standards

Section VII

Section VIII

Section VIII




Section Title





(Options and notes)

Safety Standards for Stormwater Management Basins

Section VIII

Section IX

Section IX

Section does not address non-structural strategies.

Requirement to address non-structural strategies in the Environmental Site Analysis included.


Requirements for a Site Development Stormwater Plan

Section IX

Section X

Section X



Maintenance and Repair

Section X

Section XI

Section XI

Section does not address “Minor Development.”

Section modified to include “Minor Development.”


Penalties

Section XI

Section XII

Section XII



Severability

Section XII

Section XIII

Section XIII



Effective Date

Section XIII

Section XIV

Section XIV



End of table.

Guidance Table 3


-- START OF ORDINANCE --

Section I. Scope and Purpose:

A. Policy Statement

As municipalities throughout New Jersey are developed, impervious surfaces create increased amounts and rates of stormwater runoff during precipitation events. This runoff picks up large amounts of pollutants that collect on parking lots, roadways, rooftops, and other paved or hardened surfaces, and then flows through stormwater conveyances to our streams, rivers, and beaches. The increased runoff rate and volume also lead to erosion and flooding in and downstream of developed areas

Flood control, groundwater recharge, and pollutant reduction shall be achieved through the use of stormwater management measures, including green infrastructure Best Management Practices (GI BMPs) and nonstructural stormwater management strategies. GI BMPs and low impact development (LID) should be utilized to meet the goal of maintaining natural hydrology to reduce stormwater runoff volume, reduce erosion, encourage infiltration and groundwater recharge, and reduce pollution. GI BMPs and LID should be developed based upon physical site conditions and the origin, nature and the anticipated quantity, or amount, of potential pollutants. Multiple stormwater management BMPs may be necessary to achieve the established performance standards for water quality, quantity, and groundwater recharge.

GI BMPs and LID practices not only address stormwater runoff but may also result in multiple benefits, including providing open space and beautifying neighborhoods, cooling and cleansing the air, reducing asthma and heat-related illnesses, and saving on heating and cooling energy costs.

B. Purpose

The purpose of this ordinance is to establish minimum stormwater management requirements and controls for “major development” and “minor development” as defined below in Section II.

The requirements of this ordinance are intended not only to meet but also to exceed the design and performance standards found in the New Jersey Stormwater Management Rules at N.J.A.C. 7:8. The environmental objectives of these requirements are to reduce pollution in waterways from stormwater runoff, reduce flooding and streambank erosion, and enhance groundwater recharge.

Notes:

- Minor development does not appear in the NJDEP Model Stormwater Control Ordinance for Municipalities. Municipalities may choose to implement more stringent measures, such as defining and regulating minor developments. Inclusion of minor developments, as separate from major developments, allows a municipality to set a threshold and management rules appropriate for minor developments. Including Minor development can assist municipalities in regulating stormwater management of smaller projects, which can have a significant stormwater contribution.

- Each municipality should include objectives as appropriate. For example, this ordinance includes a “stormwater retention requirement” that, in some cases, will require greater onsite capture of runoff than is required under the minimum state standards; this ordinance also applies to many developments under one acre in size, which are not covered by the minimum state standards.

- N.J.A.C. 7:8-4.2(c)(8) requires municipalities to modify land use plans and zoning ordinances as necessary to facilitate implementation of the non-structural strategies of this model ordinance. Additionally, N.J.S.A. 40:44D-93 requires municipalities to review their stormwater master plans each time they reexamine or review their land use master plans. In connection with adoption of a model ordinance, municipalities are strongly encouraged to review and update their existing land use plans and zoning ordinances to promote compliance not only with non-structural strategies, but with all provisions of this ordinance.

C. Applicability

1. This ordinance shall be applicable to the following major and minor developments:

a. Non-residential major and minor developments; and

b. Aspects of residential major and minor developments that are not pre-empted by the Residential Site Improvement Standards at N.J.A.C. 5:21.

2. This ordinance shall also be applicable to all major and minor developments undertaken by [insert name of municipality].

3. This ordinance shall also be applicable to all major and minor developments as applicable under I.C.1. and I.C.2., whether public or private.

D. Compatibility with Other Permit and Ordinance Requirements

Development approvals issued pursuant to this ordinance are to be considered an integral part of development approvals and do not relieve the applicant of the responsibility to secure required permits or approvals for activities regulated by any other applicable code, rule, act, or ordinance. In their interpretation and application, the provisions of this ordinance shall be held to be the minimum requirements for the promotion of the public health, safety, and general welfare.

This ordinance is not intended to interfere with, abrogate, or annul any other ordinances, rule or regulation, statute, or other provision of law except that, where any provision of this ordinance imposes restrictions different from those imposed by any other ordinance, rule or regulation, or other provision of law, the more restrictive provisions or higher standards shall control.

Section II. Definitions:

For the purpose of this ordinance, the following terms, phrases, words and their derivations shall have the meanings stated herein unless their use in the text of this Chapter clearly demonstrates a different meaning. When not inconsistent with the context, words used in the present tense include the future, words used in the plural number include the singular number, and words used in the singular number include the plural number. The word "shall" is always mandatory and not merely directory. The definitions below are the same as or based on the corresponding definitions in the Stormwater Management Rules at N.J.A.C. 7:8-1.2.

“CAFRA Centers, Cores or Nodes” means those areas with boundaries incorporated by reference or revised by the Department in accordance with N.J.A.C. 7:7-13.16.

“CAFRA Planning Map” means the map used by the Department to identify the location of Coastal Planning Areas, CAFRA centers, CAFRA cores, and CAFRA nodes. The CAFRA Planning Map is available on the Department's Geographic Information System (GIS).

“Community basin” means an infiltration system, sand filter designed to infiltrate, standard constructed wetland, or wet pond, established in accordance with N.J.A.C. 7:8-4.2(c)14, that is designed and constructed in accordance with the New Jersey Stormwater Best Management Practices Manual, or an alternate design, approved in accordance with N.J.A.C. 7:8-5.2(g), for an infiltration system, sand filter designed to infiltrate, standard constructed wetland, or wet pond and that complies with the requirements of this chapter.

“Compaction” means the increase in soil bulk density.

“Contributory drainage area” means the area from which stormwater runoff drains to a stormwater management measure, not including the area of the stormwater management measure itself.

“Core” means a pedestrian-oriented area of commercial and civic uses serving the surrounding municipality, generally including housing and access to public transportation.

“County review agency” means an agency designated by the County Board of Chosen Freeholders to review municipal stormwater management plans and implementing ordinance(s). The county review agency may either be:

1. A county planning agency or

2. A county water resource association created under N.J.S.A 58:16A-55.5, if the ordinance or resolution delegates authority to approve, conditionally approve, or disapprove municipal stormwater management plans and implementing ordinances.

“Department” means the Department of Environmental Protection.

“Designated Center” means a State Development and Redevelopment Plan Center as designated by the State Planning Commission such as urban, regional, town, village, or hamlet.

“Design engineer” means a person professionally qualified and duly licensed in New Jersey to perform engineering services that may include, but not necessarily be limited to, development of project requirements, creation and development of project design and preparation of drawings and specifications.

“Development” means the division of a parcel of land into two or more parcels, the construction, reconstruction, conversion, structural alteration, relocation or enlarge-enlargement of any building or structure, any mining excavation or landfill, and any use or change in the use of any building or other structure, or land or extension of use of land, for which permission is required under the Municipal Land Use Law, N.J.S.A. 40:55D-1 et seq.

In the case of development of agricultural land, development means: any activity that requires a State permit, any activity reviewed by the County Agricultural Board (CAB) and the State Agricultural Development Committee (SADC), and municipal review of any activity not exempted by the Right to Farm Act , N.J.S.A 4:1C-1 et seq.

“Disturbance” means the placement or reconstruction of impervious surface or motor vehicle surface, or exposure and/or movement of soil or bedrock or clearing, cutting, or removing of vegetation. Milling and repaving is not considered disturbance for the purposes of this definition.

“Drainage area” means a geographic area within which stormwater, sediments, or dissolved materials drain to a particular receiving waterbody or to a particular point along a receiving waterbody.

“Environmentally constrained area” means the following areas where the physical alteration of the land is in some way restricted, either through regulation, easement, deed restriction or ownership such as: wetlands, floodplains, threatened and endangered species sites or designated habitats, and parks and preserves. Habitats of endangered or threatened species are identified using the Department's Landscape Project as approved by the Department's Endangered and Nongame Species Program.

“Environmentally critical area” means an area or feature which is of significant environmental value, including but not limited to: stream corridors, natural heritage priority sites, habitats of endangered or threatened species, large areas of contiguous open space or upland forest, steep slopes, and well head protection and groundwater recharge areas. Habitats of endangered or threatened species are identified using the Department’s Landscape Project as approved by the Department’s Endangered and Nongame Species Program.

“Empowerment Neighborhoods” means neighborhoods designated by the Urban Coordinating Council “in consultation and conjunction with” the New Jersey Redevelopment Authority pursuant to N.J.S.A 55:19-69.

“Erosion” means the detachment and movement of soil or rock fragments by water, wind, ice, or gravity.

“Green infrastructure” means a stormwater management measure that manages stormwater close to its source by:

1. Treating stormwater runoff through infiltration into subsoil;

2. Treating stormwater runoff through filtration by vegetation or soil; or

3. Storing stormwater runoff for reuse.

"HUC 14" or "hydrologic unit code 14" means an area within which water drains to a particular receiving surface water body, also known as a subwatershed, which is identified by a 14-digit hydrologic unit boundary designation, delineated within New Jersey by the United States Geological Survey.

“Impervious surface” means a surface that has been covered with a layer of material so that it is highly resistant to infiltration by water.

“Infiltration” is the process by which water seeps into the soil from precipitation.

“Lead planning agency” means one or more public entities having stormwater management planning authority designated by the regional stormwater management planning committee pursuant to N.J.A.C. 7:8-3.2, that serves as the primary representative of the committee.

“Low impact development” means a development approach that uses practices to manage stormwater close to its source that results in or mimics that of natural hydrologic processes in order to preserve hydrologic and ecologic functions of receiving waters, such as preservation of natural landscape features, minimizing impervious surfaces, infiltration, evapotranspiration, or other use of stormwater. (Note, this definition was adapted from the EPA description of low impact development).

“Major development” means an individual “development,” as well as multiple developments that individually or collectively result in:

1. The disturbance of [15,000 square feet / ½ acre (21,780 square feet) / ¾ acre (32,670 square feet)] of land since February 2, 2004;

2. The creation of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more of “regulated impervious surface” since February 2, 2004;

3. The creation of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more of “regulated motor vehicle surface” since March 2, 2021 {or the effective date of this ordinance, whichever is earlier}; or

4. A combination of 2 and 3 above that totals an area of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more. The same surface shall not be counted twice when determining if the combination area equals the threshold area.

Notes:

- The threshold options provided above are suggestions only. Municipalities should evaluate the appropriate threshold level based on their knowledge and goals for the municipality.


- New Jersey Future suggests ½ acre (21,780 square feet) for item 1 of the definition and 5,000 square feet for items 2-4 of the definition. These suggestions offer enhanced stormwater management, without impacting very small projects. By selecting a disturbance threshold below the minimum 1 acre of disturbance required by NJDEP, stormwater management will become a requirement for a larger number of projects, advancing the pace of stormwater improvements. The selection of 5,000 square feet for “regulated impervious surfaces” and “regulated motor vehicle surfaces” was selected as a threshold to align with the 5,000 square feet of disturbance project limit appearing in the Soil Erosion and Sediment Control Act.

Major development includes all developments that are part of a common plan of development or sale (for example, phased residential development) that collectively or individually meet any one or more of paragraphs 1, 2, 3, or 4 above. Projects undertaken by any government agency that otherwise meet the definition of “major development” but which do not require approval under the Municipal Land Use Law, N.J.S.A. 40:55D-1 et seq., are also considered “major development.”

NOTE: The definition of major development above aligns with the definition at N.J.A.C. 7:8-1.2 and is recommended for consistency. Alternatively, a municipality may adopt the following definition, which is the minimum standard required. Municipalities that have already adopted the definition at N.J.A.C. 7:8-1.2 or another definition that goes beyond the minimum requirement should not reduce the stringency of their definition by adopting the minimum standard.

“Major development” means an individual “development,” as well as multiple developments that individually or collectively result in the disturbance of one or more acres of land since February 2, 2004.

Major development includes all developments that are part of a common plan of development or sale (for example, phased residential development) that collectively or individually result in the disturbance of one or more acres of land since February 2, 2004. Projects undertaken by any government agency that otherwise meet the definition of “major development” but which do not require approval under the Municipal Land Use Law, N.J.S.A. 40:55D-1 et seq., are also considered “major development.”

Additionally, individual municipalities may define major development with a smaller area of disturbance, a smaller area of regulated impervious or motor vehicle surface, or both.

“Minor Development” means an individual “development,” as well as multiple developments that individually or collectively result in [500 square feet / 1,000 square feet / 2,500 square feet] of disturbance, but do not meet the definition for “Major Development.”

“Motor vehicle” means land vehicles propelled other than by muscular power, such as automobiles, motorcycles, autocycles, and low speed vehicles. For the purposes of this definition, motor vehicle does not include farm equipment, snowmobiles, all-terrain vehicles, motorized wheelchairs, go-carts, gas buggies, golf carts, ski-slope grooming machines, or vehicles that run only on rails or tracks.

“Motor vehicle surface” means any pervious or impervious surface that is intended to be used by “motor vehicles” and/or aircraft, and is directly exposed to precipitation including, but not limited to, driveways, parking areas, parking garages, roads, racetracks, and runways.

“Municipality” means any city, borough, town, township, or village.

“New Jersey Stormwater Best Management Practices (BMP) Manual” or “BMP Manual” means the manual maintained by the Department providing, in part, design specifications, removal rates, calculation methods, and soil testing procedures approved by the Department as being capable of contributing to the achievement of the stormwater management standards specified in this chapter. The BMP Manual is periodically amended by the Department as necessary to provide design specifications on additional best management practices and new information on already included practices reflecting the best available current information regarding the particular practice and the Department’s determination as to the ability of that best management practice to contribute to compliance with the standards contained in this chapter. Alternative stormwater management measures, removal rates, or calculation methods may be utilized, subject to any limitations specified in this chapter, provided the design engineer demonstrates to the municipality, in accordance with Section IV.F. of this ordinance and N.J.A.C. 7:8-5.2(g), that the proposed measure and its design will contribute to achievement of the design and performance standards established by this chapter.

“Node” means an area designated by the State Planning Commission concentrating facilities and activities which are not organized in a compact form.

“Nutrient” means a chemical element or compound, such as nitrogen or phosphorus, which is essential to and promotes the development of organisms.

“Person” means any individual, corporation, company, partnership, firm, association, political subdivision of this State and any state, interstate or Federal agency.

“Pollutant” means any dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, refuse, oil, grease, sewage sludge, munitions, chemical wastes, biological materials, medical wastes, radioactive substance (except those regulated under the Atomic Energy Act of 1954, as amended (42 U.S.C. §§ 2011 et seq.)), thermal waste, wrecked or discarded equipment, rock, sand, cellar dirt, industrial, municipal, agricultural, and construction waste or runoff, or other residue discharged directly or indirectly to the land, ground waters or surface waters of the State, or to a domestic treatment works. “Pollutant” includes both hazardous and nonhazardous pollutants.

“Recharge” means the amount of water from precipitation that infiltrates into the ground and is not evapotranspired.

“Regulated impervious surface” means any of the following, alone or in combination:

1. All impervious surface within the project area limit of disturbance;

2. The total area of impervious surface collected by a new stormwater conveyance system (for the purpose of this definition, a “new stormwater conveyance system” is a stormwater conveyance system that is constructed where one did not exist immediately prior to its construction or an existing system for which a new discharge location is created);

3. The total area of impervious surface proposed to be newly collected by an existing stormwater conveyance system; and/or

4. The total area of impervious surface collected by an existing stormwater conveyance system where the capacity of that conveyance system is increased.

Notes:

- By modifying the definition from “net increase of impervious surface” to “all impervious surface within the project area,” criteria for item (2.) under the definition for “Major Development” is modified to indicate a threshold on all post-development impervious surfaces, regardless of existing condition.

- Many areas are experiencing adverse impact (flooding, poor water quality) under existing conditions. Requiring stormwater management for post-development impervious surfaces offers an opportunity for municipalities to address stormwater management impacts from a built condition.

“Regulated motor vehicle surface” means any of the following, alone or in combination:

1. The total area of motor vehicle surface that is currently receiving water;

2. A net increase in motor vehicle surface; and/or

quality treatment either by vegetation or soil, by an existing stormwater management measure, or by treatment at a wastewater treatment plant, where the water quality treatment will be modified or removed.

“Sediment” means solid material, mineral or organic, that is in suspension, is being transported, or has been moved from its site of origin by air, water or gravity as a product of erosion.

“Site” means the lot or lots upon which a major or minor development is to occur or has occurred.

“Soil” means all unconsolidated mineral and organic material of any origin.

“State Development and Redevelopment Plan Metropolitan Planning Area (PA1)” means an area delineated on the State Plan Policy Map and adopted by the State Planning Commission that is intended to be the focus for much of the State’s future redevelopment and revitalization efforts.

“State Plan Policy Map” is defined as the geographic application of the State Development and Redevelopment Plan’s goals and statewide policies, and the official map of these goals and policies.

“Stormwater” means water resulting from precipitation (including rain and snow) that runs off the land’s surface, is transmitted to the subsurface, or is captured by separate storm sewers or other sewage or drainage facilities, or conveyed by snow removal equipment.

“Stormwater management BMP” means an excavation or embankment and related areas designed to retain stormwater runoff. A stormwater management BMP may either be normally dry (that is, a detention basin or infiltration system), retain water in a permanent pool (a retention basin), or be planted mainly with wetland vegetation (most constructed stormwater wetlands).

“Stormwater management measure” means any practice, technology, process, program, or other method intended to control or reduce stormwater runoff and associated pollutants, or to induce or control the infiltration or groundwater recharge of stormwater or to eliminate illicit or illegal non-stormwater discharges into stormwater conveyances.

“Stormwater runoff” means water flow on the surface of the ground or in storm sewers, resulting from precipitation.

“Stormwater management planning agency” means a public body authorized by legislation to prepare stormwater management plans.

“Stormwater management planning area" means the geographic area for which a stormwater management planning agency is authorized to prepare stormwater management plans, or a specific portion of that area identified in a stormwater management plan prepared by that agency.

“Tidal Flood Hazard Area” means a flood hazard area in which the flood elevation resulting from the two-, 10-, or 100-year storm, as applicable, is governed by tidal flooding from the Atlantic Ocean. Flooding in a tidal flood hazard area may be contributed to, or influenced by, stormwater runoff from inland areas, but the depth of flooding generated by the tidal rise and fall of the Atlantic Ocean is greater than flooding from any fluvial sources. In some situations, depending upon the extent of the storm surge from a particular storm event, a flood hazard area may be tidal in the 100-year storm, but fluvial in more frequent storm events.

“Urban Coordinating Council Empowerment Neighborhood” means a neighborhood given priority access to State resources through the New Jersey Redevelopment Authority.

“Urban Enterprise Zones” means a zone designated by the New Jersey Enterprise Zone Authority pursuant to the New Jersey Urban Enterprise Zones Act, N.J.S.A. 52:27H-60 et. seq.

“Urban Redevelopment Area” is defined as previously developed portions of areas:

1. Delineated on the State Plan Policy Map (SPPM) as the Metropolitan Planning Area (PA1), Designated Centers, Cores or Nodes;

2. Designated as CAFRA Centers, Cores or Nodes;

3. Designated as Urban Enterprise Zones; and

4. Designated as Urban Coordinating Council Empowerment Neighborhoods.

“Water control structure” means a structure within, or adjacent to, a water, which intentionally or coincidentally alters the hydraulic capacity, the flood elevation resulting from the two-, 10-, or 100-year storm, flood hazard area limit, and/or floodway limit of the water. Examples of a water control structure may include a bridge, culvert, dam, embankment, ford (if above grade), retaining wall, and weir.

“Waters of the State” means the ocean and its estuaries, all springs, streams, wetlands, and bodies of surface or groundwater, whether natural or artificial, within the boundaries of the State of New Jersey or subject to its jurisdiction.

“Wetlands” or “wetland” means an area that is inundated or saturated by surface water or ground water at a frequency and duration sufficient to support, and that under normal circumstances does support, a prevalence of vegetation typically adapted for life in saturated soil conditions, commonly known as hydrophytic vegetation.

Section III. Design and Performance Standards for Stormwater Management Measures

A. Stormwater management measures for major development shall be designed to provide erosion control, groundwater recharge, stormwater runoff quantity control, and stormwater runoff quality treatment as follows:

1. The minimum standards for erosion control are those established under the Soil and Sediment Control Act, N.J.S.A. 4:24-39 et seq., and implementing rules at N.J.A.C. 2:90.

2. The minimum standards for groundwater recharge, stormwater quality, and stormwater runoff quantity shall be met by incorporating green infrastructure.

Note: A site may be below the area threshold for A.1 but still subject to the requirements A.2.

B. Stormwater management measures for minor development shall be designed to provide erosion control and stormwater runoff quantity control, as follows:

1. The minimum standards for erosion control are those established under the Soil and Sediment Control Act, N.J.S.A. 4:24-39 et seq., and implementing rules at N.J.A.C. 2:90.

2. The minimum standards for stormwater runoff quantity shall be met by incorporating green infrastructure.

Note: A site may be below the area threshold for B.1 but still subject to the requirements B.2.

C. The standards in this ordinance that apply to major development are intended to minimize the impact of stormwater runoff on water quality and water quantity in receiving water bodies and maintain groundwater recharge. The standards in this ordinance that apply to minor development are intended to minimize the impact of stormwater runoff by retaining the first 1-inch of precipitation on impervious surfaces onsite. The standards do not apply to new major development or minor development to the extent that alternative design and performance standards are applicable under a regional stormwater management plan or Water Quality Management Plan adopted in accordance with Department rules.

Note: Alternative standards shall provide at least as much protection from stormwater-related loss of groundwater recharge, stormwater quantity and water quality impacts of major development projects as would be provided under the standards in N.J.A.C. 7:8-5.

Section IV. Stormwater Management Requirements for Major Development

A. The development shall incorporate a maintenance plan for the stormwater management measures incorporated into the design of a major development in accordance with Section X.

B. Stormwater management measures shall avoid adverse impacts of concentrated flow on habitat for threatened and endangered species as documented in the Department’s Landscape Project or Natural Heritage Database established under N.J.S.A. 13:1B-15.147 through 15.150, particularly Helonias bullata (swamp pink) and/or Clemmys muhlnebergi (bog turtle).

C. The following linear development projects are exempt from the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity requirements of Section IV.P, Q and R:

1. The construction of an underground utility line provided that the disturbed areas are revegetated upon completion;

2. The construction of an aboveground utility line provided that the existing conditions are maintained to the maximum extent practicable; and

3. The construction of a public pedestrian access, such as a sidewalk or trail with a maximum width of 14 feet, provided that the access is made of permeable material.

D. A waiver from strict compliance from the green infrastructure, groundwater recharge, stormwater runoff quality, and stormwater runoff quantity requirements of Section IV.O, P, Q and R may be obtained for the enlargement of an existing public roadway or railroad; or the construction or enlargement of a public pedestrian access, provided that the following conditions are met:

1. The applicant demonstrates that there is a public need for the project that cannot be accomplished by any other means;

2. The applicant demonstrates through an alternatives analysis, that through the use of stormwater management measures, the option selected complies with the requirements of Section IV.O, P, Q and R to the maximum extent practicable;

3. The applicant demonstrates that, in order to meet the requirements of Section IV.O, P, Q and R, existing structures currently in use, such as homes and buildings, would need to be condemned; and

4. The applicant demonstrates that it does not own or have other rights to areas, including the potential to obtain through condemnation lands not falling under IV.D.3 above within the upstream drainage area of the receiving stream, that would provide additional opportunities to mitigate the requirements of Section IV.O, P, Q and R that were not achievable onsite.

E. Tables 1 through 3 below summarize the ability of stormwater best management practices identified and described in the New Jersey Stormwater Best Management Practices Manual to satisfy the green infrastructure, groundwater recharge, stormwater runoff quality and stormwater runoff quantity standards specified in Section IV.O, P, Q and R. When designed in accordance with the most current version of the New Jersey Stormwater Best Management Practices Manual, the stormwater management measures found at N.J.A.C. 7:8-5.2 (f) Tables 5-1, 5-2 and 5-3 and listed below in Tables 1, 2 and 3 are presumed to be capable of providing stormwater controls for the design and performance standards as outlined in the tables below. Upon amendments of the New Jersey Stormwater Best Management Practices to reflect additions or deletions of BMPs meeting these standards, or changes in the presumed performance of BMPs designed in accordance with the New Jersey Stormwater BMP Manual, the Department shall publish in the New Jersey Registers a notice of administrative change revising the applicable table. The most current version of the BMP Manual can be found on the Department’s website at:

https://njstormwater.org/bmp_manual2.htm.

F. Where the BMP tables in the NJ Stormwater Management Rule are different due to updates or amendments with the tables in this ordinance the BMP Tables in the Stormwater Management rule at N.J.A.C. 7:8-5.2(f) shall take precedence.

Table 1

Green Infrastructure BMPs for Groundwater Recharge, Stormwater Runoff Quality, and/or Stormwater Runoff Quantity


Stormwater Runoff Quality

TSS Removal

Rate

(percent)

Stormwater Runoff

Quantity

Groundwater Recharge

Minimum Separation from Seasonal High Water Table

(feet)

Cistern

0

Yes

No

--

Dry Well(a)

0

No

Yes

2

Grass Swale

50 or less

No

No

2(e)

1(f)

Green Roof

0

Yes

No

--

Manufactured Treatment Device(a) (g)

50 or 80

No

No

Dependent upon the device

Pervious Paving System(a)

80

Yes

Yes(b)

No(c)

2(b)

1(c)

Small-Scale Bioretention Basin(a)

80 or 90

Yes

Yes(b)

No(c)

2(b)

1(c)

Small-Scale Infiltration Basin(a)

80

Yes

Yes

2

Small-Scale Sand Filter

80

Yes

Yes

2

Vegetative Filter Strip

60-80

No

No

--

(Notes corresponding to annotations (a) through (g) are found following pages)

Table 2

Green Infrastructure BMPs for Stormwater Runoff Quantity

(or for Groundwater Recharge and/or Stormwater Runoff Quality

with a Waiver or Variance from N.J.A.C. 7:8-5.3)

Best

Management Practice


TSS Removal

Rate

(percent)

Stormwater

Runoff

Quantity


Minimum

Separation from Seasonal High

Water Table

(feet)

Bioretention System

80 or 90

Yes

Yes(b)

No(c)

2(b)

1(c)

Infiltration Basin

80

Yes

Yes

2

Sand Filter(b)

80

Yes

Yes

2

Standard Constructed Wetland

90

Yes

No

N/A

Wet Pond(d)

50-90

Yes

No

N/A

(Notes corresponding to annotations (b) through (d) are found on Page D-15)

Table 3

BMPs for Groundwater Recharge, Stormwater Runoff Quality, and/or Stormwater Runoff Quantity

only with a Waiver or Variance from N.J.A.C. 7:8-5.3

Best

Management Practice


TSS Removal

Rate

(percent)

Stormwater

Runoff

Quantity


Minimum

Separation from Seasonal High

Water Table

(feet)

Blue Roof

0

Yes

No

N/A

Extended Detention Basin

40-60

Yes

No

1

Manufactured Treatment Device(h)

50 or 80

No

No

Dependent

upon the

device

Sand Filter(c)

80

Yes

No

1

Subsurface Gravel Wetland

90

No

No

1

Wet Pond

50-90

Yes

No

N/A

Notes to Tables 1, 2, and 3:

(a) subject to the applicable contributory drainage area limitation specified at Section IV.O.2;

(b) designed to infiltrate into the subsoil;

(c) designed with underdrains;

(d) designed to maintain at least a 10-foot wide area of native vegetation along at least 50 percent of the shoreline and to include a stormwater runoff retention component designed to capture stormwater runoff for beneficial reuse, such as irrigation;

(e) designed with a slope of less than two percent;

(f) designed with a slope of equal to or greater than two percent;

(g) manufactured treatment devices that meet the definition of green infrastructure at Section II;

(h) manufactured treatment devices that do not meet the definition of green infrastructure at Section II.

G. An alternative stormwater management measure, alternative removal rate, and/or alternative method to calculate the removal rate may be used if the design engineer demonstrates the capability of the proposed alternative stormwater management measure and/or the validity of the alternative rate or method to the municipality. A copy of any approved alternative stormwater management measure, alternative removal rate, and/or alternative method to calculate the removal rate shall be provided to the Department in accordance with Section VI.B. Alternative stormwater management measures may be used to satisfy the requirements at Section IV.O only if the measures meet the definition of green infrastructure at Section II. Alternative stormwater management measures that function in a similar manner to a BMP listed at Section O.2 are subject to the contributory drainage area limitation specified at Section O.2 for that similarly functioning BMP. Alternative stormwater management measures approved in accordance with this subsection that do not function in a similar manner to any BMP listed at Section O.2 shall have a contributory drainage area less than or equal to 1.0 acre, except for alternative stormwater management measures that function similarly to cisterns, grass swales, green roofs, standard constructed wetlands, vegetative filter strips, and wet ponds, which are not subject to a contributory drainage area limitation. Alternative measures that function similarly to standard constructed wetlands or wet ponds shall not be used for compliance with the stormwater runoff quality standard unless a variance in accordance with N.J.A.C. 7:8-4.6 or a waiver from strict compliance in accordance with Section IV.D is granted from Section IV.O.

H. Whenever the stormwater management design includes one or more BMPs that will infiltrate stormwater into subsoil, the design engineer shall assess the hydraulic impact on the groundwater table and design the site, so as to avoid adverse hydraulic impacts. Potential adverse hydraulic impacts include, but are not limited to, exacerbating a naturally or seasonally high water table, so as to cause surficial ponding, flooding of basements, or interference with the proper operation of subsurface sewage disposal systems or other subsurface structures within the zone of influence of the groundwater mound, or interference with the proper functioning of the stormwater management measure itself.

I. Design standards for stormwater management measures are as follows:

1. Stormwater management measures shall be designed to take into account the existing site conditions, including, but not limited to, environmentally critical areas; wetlands; flood-prone areas; slopes; depth to seasonal high water table; soil type, permeability, and texture; drainage area and drainage patterns; and the presence of solution-prone carbonate rocks (limestone);

2. Stormwater management measures shall be designed to minimize maintenance, facilitate maintenance and repairs, and ensure proper functioning. Trash racks shall be installed at the intake to the outlet structure, as appropriate, and shall have parallel bars with one-inch spacing between the bars to the elevation of the water quality design storm. For elevations higher than the water quality design storm, the parallel bars at the outlet structure shall be spaced no greater than one-third the width of the diameter of the orifice or one-third the width of the weir, with a minimum spacing between bars of one inch and a maximum spacing between bars of six inches. In addition, the design of trash racks must comply with the requirements of Section VIII.C;

3. Stormwater management measures shall be designed, constructed, and installed to be strong, durable, and corrosion resistant. Measures that are consistent with the relevant portions of the Residential Site Improvement Standards at N.J.A.C. 5:21-7.3, 7.4, and 7.5 shall be deemed to meet this requirement;

4. Stormwater management BMPs shall be designed to meet the minimum safety standards for stormwater management BMPs at Section VIII; and

5. The size of the orifice at the intake to the outlet from the stormwater management BMP shall be a minimum of two and one-half inches in diameter.

J. Manufactured treatment devices may be used to meet the requirements of this subchapter, provided the pollutant removal rates are verified by the New Jersey Corporation for Advanced Technology and certified by the Department. Manufactured treatment devices that do not meet the definition of green infrastructure at Section II may be used only under the circumstances described at Section IV.O.4.

K. Any application for a new agricultural development that meets the definition of major development at Section II shall be submitted to the Soil Conservation District for review and approval in accordance with the requirements at Sections IV.O, P, Q and R and any applicable Soil Conservation District guidelines for stormwater runoff quantity and erosion control. For purposes of this subsection, "agricultural development" means land uses normally associated with the production of food, fiber, and livestock for sale. Such uses do not include the development of land for the processing or sale of food and the manufacture of agriculturally related products.

L. If there is more than one drainage area, the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards at Section IV.P, Q and R shall be met in each drainage area, unless the runoff from the drainage areas converge onsite and no adverse environmental impact would occur as a result of compliance with any one or more of the individual standards being determined utilizing a weighted average of the results achieved for that individual standard across the affected drainage areas.

M. Any stormwater management measure authorized under the municipal stormwater management plan or ordinance shall be reflected in a deed notice recorded in the {insert Office of the County Clerk or the registrar of deeds and mortgages of the county in which the development, project, project site, or mitigation area containing the stormwater management measure is located, as appropriate, to the municipality}. A form of deed notice shall be submitted to the municipality for approval prior to filing. The deed notice shall contain a description of the stormwater management measure(s) used to meet the green infrastructure, groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards at Section IV.O, P, Q and R and shall identify the location of the stormwater management measure(s) in NAD 1983 State Plane New Jersey FIPS 2900 US Feet or Latitude and Longitude in decimal degrees. The deed notice shall also reference the maintenance plan required to be recorded upon the deed pursuant to Section X.B.5. Prior to the commencement of construction, proof that the above required deed notice has been filed shall be submitted to the municipality. Proof that the required information has been recorded on the deed shall be in the form of either a copy of the complete recorded document or a receipt from the clerk or other proof of recordation provided by the recording office. However, if the initial proof provided to the municipality is not a copy of the complete recorded document, a copy of the complete recorded document shall be provided to the municipality within 180 calendar days of the authorization granted by the municipality.

N. A stormwater management measure approved under the municipal stormwater management plan or ordinance may be altered or replaced with the approval of the municipality, if the municipality determines that the proposed alteration or replacement meets the design and performance standards pursuant to Section IV of this ordinance and provides the same level of stormwater management as the previously approved stormwater management measure that is being altered or replaced. If an alteration or replacement is approved, a revised deed notice shall be submitted to the municipality for approval and subsequently recorded with the {insert appropriate Office of the County Clerk or the registrar of deeds and mortgages, as applies} and shall contain a description and location of the stormwater management measure, as well as reference to the maintenance plan, in accordance with M above. Prior to the commencement of construction, proof that the above required deed notice has been filed shall be submitted to the municipality in accordance with M above.

O. Green Infrastructure Standards

1. This subsection specifies the types of green infrastructure BMPs that may be used to satisfy the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards.

2. To satisfy the groundwater recharge and stormwater runoff quality standards at Section IV.P and Q, the design engineer shall utilize green infrastructure BMPs identified in Table 1 at Section IV.F. and/or an alternative stormwater management measure approved in accordance with Section IV.G. The following green infrastructure BMPs are subject to the following maximum contributory drainage area limitations:

Best Management

Practice


Dry Well

[0.25 / 0.5 / 0.75] acres


[0.5 / 1.0 / 1.5] acres



exceed [one / two] times the area

occupied by the BMP


[0.5 / 1.0 / 1.5] acres

Small-scale Infiltration Basin

[0.5 / 1.0 / 1.5] acres

Small-scale Sand Filter

[0.5 / 1.0 / 1.5] acres

Notes:

- The various options provided above are suggestions only. Municipalities should evaluate the appropriate level on their knowledge and goals for the municipality.

- Reducing maximum contributory drainage areas will lead to more stormwater best management practices that are distributed on the site, a key component of low impact development. This reduces the risk of damage if any one system is overloaded or experiences failure.

- Reduced loading rates onto pervious pacing systems maintain the intended benefits of the system. Additional areas loaded onto the porous pavement systems increases the potential for sediment and pollutant loading, which overtime can lead to failure of systems.

3. To satisfy the stormwater runoff quantity standards at Section IV.R, the design engineer shall utilize BMPs from Table 1 or from Table 2 and/or an alternative stormwater management measure approved in accordance with Section IV.G.

4. If a variance in accordance with N.J.A.C. 7:8-4.6 or a waiver from strict compliance in accordance with Section IV.D is granted from the requirements of this subsection, then BMPs from Table 1, 2, or 3, and/or an alternative stormwater management measure approved in accordance with Section IV.G may be used to meet the groundwater recharge, stormwater runoff quality, and stormwater runoff quantity standards at Section IV.P, Q and R.

5. For separate or combined storm sewer improvement projects, such as sewer separation, undertaken by a government agency or public utility (for example, a sewerage company), the requirements of this subsection shall only apply to areas owned in fee simple by the government agency or utility, and areas within a right-of-way or easement held or controlled by the government agency or utility; the entity shall not be required to obtain additional property or property rights to fully satisfy the requirements of this subsection. Regardless of the amount of area of a separate or combined storm sewer improvement project subject to the green infrastructure requirements of this subsection, each project shall fully comply with the applicable groundwater recharge, stormwater runoff quality control, and stormwater runoff quantity standards at Section IV.P, Q and R, unless the project is granted a waiver from strict compliance in accordance with Section IV.D.

P. Onsite Retention and Groundwater Recharge Standards

1. This subsection contains the minimum design and performance standards for onsite retention and groundwater recharge for Major Developments as follows:

2. The design engineer shall, using the assumptions and factors for stormwater runoff, onsite retention, and groundwater recharge calculations at Section VI, the following criteria that results in the greatest infiltration volume:


ii. Demonstrate through hydrologic and hydraulic analysis that the increase of stormwater runoff volume from pre-construction to post-construction for the 2-year storm is infiltrated; or

iii. Demonstrate through hydrologic and hydraulic analysis that the onsite retention volume of [1.0 / 1.25 / 1.5] inches over all impervious surfaces is infiltrated or retained onsite.

Notes:

- This modification requires a volume equal to or greater than the precipitation depth over impervious surfaces to be infiltrated or retained onsite.

- Infiltration of stormwater from onsite impervious will achieve several stormwater management goals, including reduced flooding, improved water quality, and increased groundwater recharge.

3. This groundwater recharge requirement does not apply to projects within the “urban redevelopment area,” or to projects subject to 4 below.

4. The following types of stormwater shall not be recharged:

i. Stormwater from areas of high pollutant loading. High pollutant loading areas are areas in industrial and commercial developments where solvents and/or petroleum products are loaded/unloaded, stored, or applied, areas where pesticides are loaded/unloaded or stored; areas where hazardous materials are expected to be present in greater than “reportable quantities” as defined by the United States Environmental Protection Agency (EPA) at 40 CFR 302.4; areas where recharge would be inconsistent with Department approved remedial action work plan or landfill closure plan and areas with high risks for spills of toxic materials, such as gas stations and vehicle maintenance facilities; and

ii. Industrial stormwater exposed to “source material.” “Source material” means any material(s) or machinery, located at an industrial facility, that is directly or indirectly related to process, manufacturing or other industrial activities, which could be a source of pollutants in any industrial stormwater discharge to groundwater. Source materials include, but are not limited to, raw materials; intermediate products; final products; waste materials; by-products; industrial machinery and fuels, and lubricants, solvents, and detergents that are related to process, manufacturing, or other industrial activities that are exposed to stormwater.

5. Where the onsite retention volume cannot be infiltrated, reused, or evapotranspirated, the onsite retention volume shall be slow released at a rate of not more than 0.02 cfs per acre of drainage area to mimic receiving water groundwater discharge flow. The retention volume shall be released within 72 hours.

Q. Stormwater Runoff Quality Standards

1. This subsection contains the minimum design and performance standards to control stormwater runoff quality impacts of major development. Stormwater runoff quality standards are applicable when the major development results in:

i. Creation of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more of regulated motor vehicle surface, and/or

ii. Creation of [1,000 square feet / 5,000 square feet / 10,000 square feet] or more of regulated impervious surface.


i. Eighty percent TSS removal of the anticipated load, expressed as an annual average shall be achieved for the stormwater runoff from regulated motor vehicle surfaces and regulated impervious surfaces.

ii. If the surface is considered regulated motor vehicle surface because the water quality treatment for an area of motor vehicle surface that is currently receiving water quality treatment either by vegetation or soil, by an existing stormwater management measure, or by treatment at a wastewater treatment plant is to be modified or removed, the project shall maintain or increase the existing TSS removal of the anticipated l

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